<!DOCTYPE html>
<html lang="en">
<head>
    <meta charset="UTF-8">
    <meta name="viewport" content="width=device-width, initial-scale=1.0">
    <title>Topology Drag and Drop Editor</title>
    <style>
        #canvas {
            border: 1px solid black;
            width: 100%;
            height: 600px;
        }
        .property-editor {
            position: absolute;
            top: 10px;
            right: 10px;
            width: 300px;
            padding: 10px;
            border: 1px solid #ccc;
            background-color: #f9f9f9;
            display: none;
        }
        .resize-handle {
            cursor: nwse-resize;
            fill: #ccc;
        }
    </style>
</head>
<body>
    <div id="canvas"></div>
    <button id="add-node">Add Node</button>
    <div class="property-editor" id="property-editor">
        <h3>Node Properties</h3>
        <textarea id="json-editor" rows="10" cols="30"></textarea>
        <button id="save-properties">Save</button>
    </div>
    <script src="https://d3js.org/d3.v7.min.js"></script>
    <script src="main-1.js"></script>
</body>
</html>
